Heavy contaminant accumulates on the insulator surface of porcelain long rod insulator in condition of heavy pollution and brief rain

which poses a flashover hazard to the power system. Consequently

taking Xuzhou city

which is in semi-humid area and where a large amount of porcelain long rod insulators are used and porcelain long rod insulators and disk type porcelain insulators are hung up on the Daiyao 5667 transmission line for several months

as an investigation object

we compared the contaminant difference between these two insulators. The contamination characteristics of porcelain long rod insulator were analyzed by wind tunnel artificial contamination tests and a simulation model. According to the measurement of insulators hung up

more contaminants accumulate on the surface of porcelain long rod insulator than on the disk type porcelain insulator in condition of brief rain from Feb. to Apr. in 2016. The ESDD ratio of porcelain long rod insulator to disk type porcelain insulator is 3.4:1. The ESDD and NSDD are both greater than that obtained on porcelain long rod insulator based on the wind tunnel artificial contamination tests. Furthermore

more contaminants accumulates on the porcelain long rod insulator with a smaller rod diameter. Due to the open umbrella structure of porcelain long rod insulator

there is larger area ratio which is stroke by the contamination particulate. Porcelain long rod insulator in transmission line should be cleaned in time especially in the heavy pollution and brief rain area.